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I know I took a pic of a thread detailing the differences between the jeep 3.6, 3.8 and the dyno number were way off than the advertised hp of the two. I would have sworn motech had done them but after an hour of looking for the thread and finding nothing. Anybody remember this? I want to say the 3.8 was around 135 and the 3.6 was not much better.
 

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Random Dude
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I know I took a pic of a thread detailing the differences between the jeep 3.6, 3.8 and the dyno number were way off than the advertised hp of the two. I would have sworn motech had done them but after an hour of looking for the thread and finding nothing. Anybody remember this? I want to say the 3.8 was around 135 and the 3.6 was not much better.
You talking about crank horsepower or wheel horsepower vs. "advertised HP"? :dunno:

Here's a necro-crosspost of @ALASHA stating ~50% loss at the wheels about a decade ago (see bold red portion):

356 rwhp out of a 345 hp 5.7? :shaking:



I can tell you that the stock Rubicon drivetrain on stock Rubi tires losses right about 50% as measured at the wheels, so the 3.8L v6 makes 205 at the crank, I had 106 measured at the wheels.

THEORETICALLY, apply the same loss to a 345 5.7 and you SHOULD see ~172 at the wheels.
Here's a graph from a thread in 2012 (linked):



I thought there was a thread recently with big-engine dyno numbers, but can't find it :(
Maybe it was a meltdown thread and the OP was a HGPD-ing, no-class-havin' mu'fugger :laughing:


EDIT: Apparently Ripp claims/sees (or did 5 years ago) 33% drivetrain loss, based on this post:

Cool man!

445hp = estimated crank HP?

295 at the wheels (assuming RIPPs oft quoted 33% drivetrain loss)?
OK, I'm done googling shit :laughing: - here's my secret: MAGIC FINDY-LINK
 

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Real world averages are 30-35% drivetrain loss on a JKU ......

Have seen as much as 45% on some personally . bot those were new tons with big heavy tires and wheels .
After some berakin' i would expect to see better numbers , but not much .
The averages are less with light shit , more with heavy shit .
 

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I know the original @ALASHA dyno was done here in Colorado Springs at approx. 5800ft. I know our air sucks here. I don't know if that is corrected for DA.
 

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Random Dude
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I know the original @ALASHA dyno was done here in Colorado Springs at approx. 5800ft. I know our air sucks here. I don't know if that is corrected for DA.
Good call, dude! :beer:

If true, that reconciles the "30-35%" folks with ALASHA's ~50% results.

Also, per my (NIST-traceable, meticulously calibrated) butt dyno: going from ~sea-level to 6-7,000 ft., the 6 squirrels under the hood seem ~20-30% less enthusiastic :laughing:
 

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I know the original @ALASHA dyno was done here in Colorado Springs at approx. 5800ft. I know our air sucks here. I don't know if that is corrected for DA.
Went back to my original thread to double check. Those numbers were with a full atmospheric correction. Pulled on a Dyno Dynamics load bearing dyno which tend to read lower than others.


Also phuck photobucket.
 

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Um, you're going to have to share a bit more about the build..........like everything.:thefinger:




It’s a 2013 10th anniversary with full custom suspension, oris, dynatrac 40 spline 60/80 combo with big bell rcvs. Custom cage, prp seats, built southern hotrod nag1 tranny, atlas tcase. Running right at 1000 Hp at the crank.


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Very clean. How are it's street manners?

Surprisingly not bad. We used a mmx smooth boost controller so we can basically turn the power down if needed. When all the way down it feels about like a stock Jeep. The suspension is extremely stable and almost no body roll but with the way I have the ori struts adjusted for Offroad I do get a ton of front end lift due to the rear suspension geometry. If you have Instagram I post there for the most part.

https://www.instagram.com/p/B8PtvRDnJYE/?igshid=11tl3qz2akdga


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2008 JKU w/LS 5.3
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My 5.3 (Gen iv lc9) dynod 258hp/264tqx to the wheels on 35s with 3.73 gears. That is a stock truck motor with 120k miles on it. mild tune, headers, intake exhaust is all that was added.
364755
 

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If I remember correctly, the 3.8L with a RIPP puts down ~250hp at the wheels, with an auto, 37“ tires, and 5.38’s.
This is exactly what I am running.
If I could ”regear” the transmission, (damn 4-speed!), I’d do just that.

I must admit, the RIPP has made a major difference on my Rubi.
I live in west Georgia where there are a lot of hills. On a particular route that I commonly take, when my Jeep was stock, it would downshift from 4th to 2nd gear to get up some hills and still lose speed. With the RIPP it only goes down to 3rd gear and holds speed going up the same hills.

I used to be a proponent for RIPP, but now that I have a higher income, I am planning to take it to MoTech to get a Gen IV 6.2 swap. I’m just tired of the shitty transmission, and waiting to hit 2500 RPM before the boost really hits.
 
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